Glance at the publications credited to Louis E. Brus and it immediately becomes clear that the Samuel Latham Mitchell Professor of Chemistry at Columbia University has made wide-ranging contributions to physical chemistry. What isn’t obvious is that a large number of his scholarly papers have been cited by fellow scientists hundreds of times each. Reflecting on the breadth and importance of Brus’s scientific investigations, his Columbia chemistry colleague, Bruce J. Berne, asserts that Brus’s “sustained creativity and novel problem choices have had wide impact” on chemistry.

Early in his research career, Brus studied gas-phase sodium iodide to learn how photodissociation produces excited sodium atoms and to understand the fundamental chemistry of this species. He later worked in laser research, concentrating on basic studies for developing infrared chemical lasers.

Continuing with laser-based investigations, Brus studied molecular spectroscopy and dynamics of molecules in gas matrices by using laser light to excite and then probe the behavior of those molecules. The work revealed key processes through which excited molecules undergo vibrational relaxation. He also demonstrated how the “cage effect” controls molecular dynamics and affects spectra of excited-state species. In addition, Brus and coworkers developed laser-driven pump-probe Raman scattering techniques to characterize structures of complex reaction intermediates central to solution-phase photochemistry.

A critical point in Brus’s research career came while he and coworkers at AT&T Bell Laboratories, in Murray Hill, N.J., were studying redox reactions on the surfaces of photoexcited semiconductors. To increase the surface area on which those reactions could occur, the researchers used colloidal synthesis methods to prepare tiny semiconductor particles. The team observed that certain particle properties—most notably the electronic band gap—varied with particle size. That discovery motivated several research groups to begin investigating semiconductor nanocrystals, also known as quantum dots.

As the field began to grow and scientists recognized the particles’ potential use in applications ranging from optoelectronics to biology, Brus and coworkers at Bell Labs, and later at Columbia, continued conducting groundbreaking experiments with quantum dots. For example, they investigated luminescence from single nanocrystals and explained the curious blinking phenomenon—the intermittent light emission—associated with those particles. The group also developed advanced microscopy methods for studying the particles.

More recently, Brus’s team has been investigating properties of other nanoscale materials including silver, transition-metal oxides, and carbon nanotubes. The group is developing methods for using these nanoscale objects as microscopic antennae for novel, high-sensitivity detectors.

Brus, 67, completed a bachelor’s degree in chemical physics at Rice University in 1965 and earned a doctorate four years later from Columbia. For four years, he served as a lieutenant in the Navy conducting research at the Naval Research Laboratory, in Washington, D.C., and then embarked on a 23-year career at Bell Labs. In 1996, he joined the faculty at Columbia, where he continues to conduct research.

For his contributions to science, Brus was elected to the National Academy of Sciences in 2004 and has been honored with several awards including the Irving Langmuir Prize in Chemical Physics, the ACS Chemistry of Materials prize, and the 2008 Kavli Prize in Nanoscience.

Brus will present the award address before the Division of Physical Chemistry.